localisation Flashcards
what is localisation?
1) Localisation of function is the theory that a specific part of the brain is
responsible for a certain behaviour.
2)However, a lot of functions are also widely distributed meaning different parts
of the brain have to work together to create behaviour.
3)Therefore, damage to one part of the brain means that there will be damage to
that brain function
study 1
Wilder Penfield
Aim
to treat patients with severe epilepsy by destroying nerve cells that initiated the seizure
Procedure
-before conducting the surgery, he would stimulate various parts of the brain while the patient was still conscious.
-he would observe the effects the stimulations had on their behaviour.
Results
-Wilder Penfield created a map of the sensory and motor context known as the CORTICAL HOMUNCULCUS
Conclusion
An original model of the body within the brain was created. which proved that psychological functions have directly corresponding regions in the brain. that is, strict localisation.
Evaluation
+ provided insight -no consent
-protection from
harm
link to study 2
however, localisation isnt strict as seen in…
STUDY 2
Maguire et al
Aim
to examine whether structural changes could be detected in the brains of people with extensive experience in spatial navigation
Procedure
+ structural MRI scans were obtained
+ 16 right-handed male London Taxi drivers participated
+ all of them had been driving for over 1.5 years
+ scans of 50 healthy right-handed male non taxi drivers were obtained for comparison
+ mean age did not differ in both groups
Results
1) increased grey matter was found in the brains of taxi drivers compared with the controls in 2 regions, THE RIGHT AND LEFT HIPPOCAMPUS
2) the increased volume was found in the posterior (rear) hippocampus
3) changes with navigation experience–> a correlation was found between the amount of time spent being a taxi driver and the volume of the right posterior hippocampus
Conclusion
the results provide evidence for structural differences between the hippocampus of London taxi drivers and control groups.
this suggests that extensive practice in spatial navigation affects the structure of the hippocampus
Evaluation
+ proved plasticity and localisation
+ used mri scans
+ lots of controls
- correlational study
- few taxi drivers
- mri scans can be uncomfortable